Pump impeller



Feb. 16, 1954 Y MclNTYRE 2,669,188

PUMP IMPELLER Filed March 14, 1950 wfzuczi Patented Feb. 16,1954

"Brouwer" D; McIntyre, Monrne, .'iMieh;, 'assignor. "to 'Patent"'-Deve1opment Company, Monroe.

Mich, a partnership 60mins; 1'.

This. invention, relates generally to, fluid pumps ancLmore. particularly toa novel; impeller. con.- stru'ction forv such pumps.

L'Itris an object of this invention to. provide. an

-impeller forzaifluid pump. which can. be. rotated .or.. started with a relatively low "driving-motor load and. whiohwill efii ciently pump or. circulate .fl'u'id without. slippage or by-passing of. the. fluid after 'it. has. reached apredetermined. speed.

I'Itlis. a. son, further object. of this invention .to provide. an. impeller offthe. aforementioned type, in whichtheblades are madeof flexible. material and. are: normally disposed, when .the. impeller is i'not. being driven, with 5 their end, and. side. faces positioned relative. to, 'thewallsoffthe pump. housing, chamber. so .thatf'fl'uidcan move ftherepast, bilt. willideflectv on 'yield when-the impeller rotating, at a predetermined speed so as to sealingly engage the walls ofthe housing. and

prevent av flow of fluid between the. impeller blades and pump housing chamber.

YIti'sa still further object. of thisinvention. to provide a. pump. impeller of the aforementioned typeflwhi'ch is-so constructedfthatL-itwihf deflect onyi'eld'i'only aj'desired amount. so as. to remain iniengagem'ent with the walls offthe' housing. un-

ttil the r'ota'tive speed ofithe'impeller' is. reduced beyond a. predetermined speed. or is completely t stopped.

Itiis a still; further. objectv oi this. inveiitiontoprovide an impeller of the aforementioned. type,

'Which'mayj be. molded. as a one-piece article.

"It is a still further. object offthis invention. to

provide an'impe'ller ofithe aforementiond'type,

which may be used'with' a fluid pump havinggi'ts t'tfl'uid, intake or inlet at" either the center or side of thehousing. 7

"It is a still further object" of this invention to "provide an "impeller of the'aforemen'tioned type efficient" in operation, durabledn use, relatively inexpensive to manufacture; and which will" provide longer-life for the impeller driving motorthanhas been"heretofore'possible;

Theseand otherobjectsof this invention will become apparent irorrrthe following detaiIedFde- *scriptiom' taken "in conjm-IctiQn' With the accompanyingdrawing; which:

Figure 11 is a view, partially im'seetion and par- *ti'allyiir elevation; of a fluid-'pump ineorporating the imp'ellen i of .this inventi'on; and 'showingsthe impeller i its normal; at rest position i 'Fi'gi-i 2a a sectional: View: of; the. structure 1 il- --1usimated;ini Figure l5,' ii9;k61t;a10ngith6i liner 21 2 ilmt'i tially inaelevation similar .tol Figural; butfshow- 'thec position of; the.- impeller blades when.' the impeller rotating at. a predetermined. speed and-circul'atingunuid; and

Y Riga. 4:..is a sectionaLview of the. structure ill-us- .tratedin Eigi tit-taken along the line. i 4 thereof Referring; now to the. drawing,.lit will beseen that, all fiuidf illustrated Which. includes a .housing;5,=.of.any-suitable type The, housing illustrated isproy'idedwitha chamber 'l ha'vingan'an- .nulan side wall 9 andilielatively fiat-endiwlalls. H.

The. housing) 51 has a" fluid; inlet L3. which. communicat-eswith one side. of -chamber. 1 adjacent the ,howeverf, be. appreciated. that the inletand outlet could. be .lncated in. anydesird. relationship with respect to the charniber. J For. example. the inlet-could lee-located atlthe center of the housing Without. departing. from the scope of the invention. .A. shafti ll is rotatably: supported in the .endrwallsfll I ofthehousing 5,.in any suitable -manner,.and has animpellen [amounted thereon and connected therewith. The shaftv I! is adapted-to be -retatably drivenby a suitable motion-and; a plur alityof. outwardly proj ecting,,. circumferentially spaced blade. portionsi 2-1. 'Ifhe blades 21 extend... outwardly from the hub portionwarid-- areadirectd away from radial. lines extending-1outwardly from.theaxis of rotation of the impeller; andrshaft Ill in the. direction of re.-

tation of theimpeller. .Qne..faeej23 of each blade portion. is concave (s.eeliig. andis of. a shorter extent-than. the. other .iace'. 24;; which. .is, of. a convex; shape {The face: terminatesat its. inner flheimpeller rtfitis prefei'ably molded as-a one.-

. piecetairticlezin-.a; rubbenmolding; machine.- or the like, so.kthatstheablades are curved as illustrated in; Fig. lqgand the outenends-29- thereof willsnot sea1-ingly: i engagelthe annula-r sidetwall 9 of the chamber 1. The outer ends 2.9 aredisposed, in. a cylindrical path, the radius,-ofi whichmis;lessthan the. radius ot-the-pumpi chamber walk 9; measured 'ffronmthe same scepter: or: a is,.- of. rotation .of .atheiimpeilerh I mkewisex-thei-hladess arescunvedsin ism viewer-partially a-sectiom ands-pan -thewpposite;iplena anddcrnmthe concaveraces 23 and convex faces 24, as can be seen in Fig. 2, so that the side faces 3| of the blades will not sealingly engage the end walls I l of the housing chamber. That is, the blades 2| are curved in a transverse plane relative to the end walls II and are of a width less than the distance between the chamber end walls, so as to provide a space between the blades and the end walls. The amount of space between the end faces of the blades and the chamber side wall and the side faces of the blades and the chamber end walls may vary in accordance with the pump construction and requirements, but it is important that the impeller not sealingly engage the chamber walls when the impeller is at rest.

When fluid is flowing into the housing chamber I and the impeller is rotatably driven by the motor, centrifugal force and the force of the fluid acting against the impeller blades will cause the blades to yield or deflect and in effect straighten out or expand so that, at a predetermined speed and/or fluid pressure, the end faces 29 of the blades will sealingly engage the annular side wall of the chamber 9 and so that the side faces'3i will sealingly engage the end walls of the housing 5. That is, the curvature of the blades, in both planes, previously pointed out, is eliminated or reduced so that the blades will properly engage the housing chamber walls, and fluid can no longer flow between the impeller and chamber walls. The construction of the blades, as previously pointed out, is such that when the blades are deflected into engagement with the chamber walls, suflicient stiffness or resistance is present in the blades to prevent them from moving out of engagement with the walls in the opposite direction from their original position. This results from the shape and manner in which the blade portions are interconnected so that portions of the impeller which include the sloping faces 24 act in tension and portions of the impeller which include the faces 23 act in compression to prevent the blades from moving beyond engagement with the walls of the chamber and thereby maintain the proper blade and Wall engagement until the rotation of the impeller is decreased below a predetermined speed, or completely stopped.

Thus, when the rotation of the impeller begins, fluid flowing to the chamber through the inlet l3 may escape past the end and side faces of the impeller so that there will be a relatively li ht load on the driving motor during the startup operation. However, as the speed of the impeller increases so that the impeller blades are subjected to greater centrifugal force and are subjected to more force from the fluid, the blades Will move into sealing engagement with the walls of the housing and will thus circulate fluid from the inlet l3 to the outlet 15, in an exceptionally efficient manner, so that the pump will circulate the water at high speeds in the same manner as if the impeller were solid and were engaging the walls of the housing chamber at all times. It can thus be appreciated that the impeller of this invention will operate smoothly and efiiciently and will not overload or tend to excessively wear the driving motor therefor, especially in the start-up stage of operation, which is the hardest on the driving motor.

What is claimed is:

l. A fluid pump including a housing having an annular chamber therein and a fluid inlet and an outlet, animpeller including a hub portion rotatably supported in said chamber and including a plurality of circumferentially spaced resilient blades extending outwardly from said hub portion and directed away from radial lines ex tending outwardly from the impeller axis of rotation, in the direction of rotation of said impeller, the outer ends of said blades being disposed in a cylindrical path, the radius of which is less than the radius of the pump chamber measured from the same center, the resiliency of said impeller blades being such that when the impeller is rotating at a predetermined speed and circulating fluid through the chamber, the blades will move toward said radial lines and into substantial sealing engagement with the Walls of said housing chamber.

2. A fluid pump including a housing having an annular chamber therein and a fluid inlet and an outlet, an impeller including a hub portion rotatably supported in said chamber and including a plurality of circumferentially spaced resilient blades extending outwardly'from said hub portion and directed away from radial lines extending outwardly from the impeller axis of rotation, in the direction of rotation of said impeller, the outer ends of said blades being disposed in a cylindrical path, the radius of which is less than the radius of the pump chamber measured from the same center, the resiliency of said impeller blades being such that when the impeller is rotating at a predetermined speed and circulating fluid through the chamber, the blades will move toward said radial lines and into substantial sealing engagement with the walls of said housing chamber, and means controlling the movement of said blades so as to prevent the end and side faces of the blades from moving out of engagement with the walls of the chamber until the rotation of the impeller diminishes below a predetermined speed.

3. A fluid pump including a housing having a chamber defined by an annular wall and substantially flat end walls, a fluid inlet and an outlet communicating with said chamber, an impeller including a hub portion rotatably supported in said chamber and including a plurality of circumferentially spaced resilient blades extending outwardly from said hub portion and directed away from radial lines extending outwardly from the impeller axis of rotation, in the direction of rotation of said impeller, the outer ends of said blades being disposed in a cylindrical path, the radius of which is less than the radius of the pump chamber measured from the same center, said blades being curved in a transverse plane relative to said end walls and being of a width less than the distance between said chamber end Walls so as to provide a space between the blades and said end walls, said impeller blades being of such resiliency that when the impeller is rotating at a predetermined speed the blades will move into substantial sealing engagement with the annular wall and the end walls of the housing chamber so that the impeller will effectively move fluid from the inlet to the outlet.

4. A fluid pump including a housing having a chamber therein, an impeller rotatably supported in said chamber and including a plurality of spaced resilient blades adapted to sealingly engage the walls of the chamber, said blades extending toward the walls of said chamber along paths curved both radially and transversely and being of a length and width relative to the dimensions of the housing chamber such as not to engage the walls of said chamber, the resiliency of said blades being such that the blades will be deflected from their curved paths toward straight elongated paths, and thus into sealing engagement with the walls of the chamber when the impeller is rotating at a predetermined speed and circulating fluid.

5. A fluid pump including a housing having an annular chamber therein and a fluid inlet and outlet, an impeller including a hub portion rotatably supported in said chamber and including a plurality of circumferentially spaced resilient blades extending outwardly from said hub portion and being radially curved, with the concave face thereof forming the front face of each blade relative to the direction of rotation of the impeller, the outer ends of said blades being disposed in a cylindrical path, the radius of which is less than the radius of the pump chamber, measured from the same center, the resiliency of said impeller blades being such that when the impeller is rotating at a predetermined speed and circulating fluid through the chamber the blades will move toward said radial lines and into substantial sealing engagement with the walls of said housing chamber.

6. A fluid pump including a housing having a chamber defined by an annular wall and substantially flat end walls, a fluid inlet and an outlet communicating with said chamber, an impeller including a hub portion rotatably supported in said chamber and including a plurality of circumferentially spaced resilient blades extending outwardly from said hub portion, said blades be- 6 ing radially curved, with the concave face thereof forming the front face of each blade relative to the direction of rotation of the impeller, the outer ends of said blades being disposed in a cylindrical path, the radius of which is less than the radius of the pump chamber, measured from the same center, said blades being also curved in a transverse plane relative to said end walls and being of a width less than the distance between said chamber end walls so as to provide a space between the blades and end walls, said impeller blades being of such resiliency that when the impeller is rotating at a predetermined speed the blades will move into substantial sealing engagement with the annular wall and the end walls of the housing chamber 50 that the impeller will effectively move fluid from the inlet to the outlet.

BROUWER D. McINTYRE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 145,617 Brear Dec. 16, 1873 2,203,974 Weinhardt June 11, 1940 2,455,194 Rumsey Nov. 30, 1948 2,466,440 Kiekhaefer Apr. 5, 1949 2,537,502 Yingling Jan. 9, 1951 FOREIGN PATENTS Number Country Date 574,572 Great Britain Jan. 10, 1946 

